Individual and contextual variation in spatial voting

Party identification and issue preferences are central explanatory factors in many models of voting choice. Their effects on party preferences are usually conceived to be additive. That is, party identification is expected to increase the likelihood of supporting one’s preferred party, but not to make voters more or less responsive to issues or ideology. This paper suggests an alternative model in which party identification moderates the impact of issue preferences on the vote. This hypothesis is derived from dual-process models of opinion formation. These models suggest that party identifiers should be more likely to evaluate parties in a heuristic fashion, based on party labels, and that they should be less sensitive to parties ’ issues positions. In addition, I expect the moderating role of party identification to be conditioned by voters ’ level of political sophistication and by the issue-specific degree of party polarization. These hypotheses are tested with data from four recent Dutch election studies.